Moles are caused when cells in the skin, called melanocytes, grow in clusters or clumps with tissue surrounding them. Melanocyte cells produce melanin, the natural pigment that gives your skin its color. Normally, melanocytes are distributed evenly throughout your skin.

Most moles are harmless and don't require special care, but some people have unusual-looking moles, called dysplastic nevi, which are more likely to turn cancerous than ordinary moles are.

Dec. 06, 2011

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